Recent studies have indicated that the contamination of both wet and dry household surfaces with potentially pathogenic quantities of bacteria is widespread. Following a study of bacterial flora in 200 homes, Scott et al., in J. Hyg. Camb., Vol. 89, 279 (1982) concluded that improved decontamination procedures are necessary, particularly at sites which are repeatedly wetted, such as the surfaces of sinks, toilets, draining boards, stoves, washing machines and the like. However, controlled in use tests employing dilute aqueous detergents at kitchen and bathroom sites achieved no observable reduction in microbial contamination, while application of aqueous hypochlorite and phenolic disinfectant compositions only produced a significant reduction in contamination levels for 3-6 hours. In their evaluation of disinfectants in the domestic environment, Scott et al., J. Hyg. Camb., Vol. 92, 193 (1984) hypothesized that the rapid recontamination was due both to re-usage of surfaces such as toilets and to the local multiplication of residual colonies at repeatedly wetted sites such as sinks.
Compositions intended for the controlled release of a disinfectant from a film of a stabilized hydrophilic polymer are disclosed in U.S. Pat. No. 3,966,902. The polymer complex is stabilized as a metal complex by the addition of an inorganic aluminum, zirconium or zinc salt such as aluminum chlorohydrol to the polymerization mixture. The stabilization adjuvant is necessary due to the fact that upon contact with water, films of simple hydrogels become highly swollen and rapidly elute their additives. Furthermore, dry films both simple and metal-complexed hydrogels do not adhere well to ceramic and other hard surfaces and lose their adhesion completely when wetted.
Thus, a need exists for a disinfectant composition capable of forming a polymeric film on hard surfaces such as those formed of ceramics, glass, formica, plastics, metals and the like, which film can entrain a germicidal substance such as a quaternary ammonium salt or a phenolic. A need also exists for a composition capable of yielding a transparent film having strong adhesion to the substrate surface and high resistance against abrasive removal during commonly-employed cleansing procedures. A further need exists for a disinfectant film capable of providing extended protection against microbial contamination.